1. Field of the Invention
The present invention relates to an organic light emitting display device.
2. Description of the Related Art
A recent trend of display apparatuses is for the display apparatuses to be thin and mobile. Among the display apparatuses, organic and inorganic light emitting display devices are emissive type display apparatuses that have wide viewing angle, high contrast, and short response time. Also, among organic and inorganic light emitting display devices, an organic light emitting display device (in which a light emitting layer is formed of an organic material) has high brightness, low driving voltage, short response time, and can be multi-colored.
An organic light emitting display device can be a flat panel display device that is formed to be lightweight and thin so that the flat panel display device can be mobile and used in an outdoor environment. However, when images are viewed in the outdoor environment, contrast and visibility of the images displayed on the flat panel display device may be reduced due to strong external light such as sunlight. Even in an indoor environment, the visibility of the images displayed on the flat panel display device may be reduced due to fluorescent lamps.
Therefore, in order to reduce (or protect against) the reduction of visibility of images due to external light, a film type polarized plate may be attached to the entire surface of a flat panel display device. In this way, the reflection of external light that enters into the flat panel display device is reduced (or prevented). As a result, brightness of the reflected external light is reduced, and thus, the reduction of visibility of images due to external light is reduced (or prevented).
However, in the case of a conventional flat panel display device, the film type polarized plate attached to the entire surface of the flat panel display device is manufactured by bonding many layers of films. Thus, the manufacturing process is complicated, which leads to high manufacturing costs and increase in thickness of the flat panel display device. As such, a thin flat panel display device may not be realized. Accordingly, there is a need to develop a method to increase contrast of the organic light emitting display device without using a film type polarized plate (or a circular polarized film) and also to protect (or prevent) the organic light emitting display device from being damaged by external impact.